It is appropriate at this stage to look at the relationship between water supply and health. We have seen how in developing countries people living in rural areas have less access to safe drinking water. The World Health Organization (WHO) has played an important in promoting the spread of health education, including advice about the importance of clean water supply and sanitation. It is estimated that 80% of the world’s diseases result from unclean water and inadequate sanitation. Limitations to improve the situation in most developing countries is the lack of finances, the rapid growth of population and the spreading of squatter settlements in urban areas.
Many diseases are carried to people through poor standards of hygiene and infected water supplies. Bilharzia is the common disease in most parts of the tropics. The bilharzia snails live in shallow polluted still waters. Small worms living in these snails spread the disease. The worms may enter people’s bodies through the skin and may live in their intestines. Eggs of the worms may then be passed into water via excreta. In the water the eggs hatch and become worms, and worms may again enter another human body through the skin.
Life cycle of Bilharzia worm
The cycle is encouraged if no proper use of sanitation is used.